Modular cushioning mechanism



- June 2, 1970 P. o. ROBARDS 3,515,287

MODULAR CUSHIONING MECHANISM 2 Sheets-Sheet 1 Filed Jan; 5, 1968 27 INVENTOR EST-0N O. Rosmps ATTORNEY United States Patent 3,515,287 MODULAR CUSHIO'NING MECHANISM Preston 0. Robards, Roselle, Ill., assignor to Portec, Inc., Chicago, Ill., a corporation of Delaware Filed Jan. 5, 1968, Ser. No. 695,926 Int. Cl. B61g 9/04, 9/06, 9/10 US. Cl. 213-37 9 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to cushioning devices and more particularly to a cushion mechanism of the modular type for use in railway car draft rigging.

A principal disadvantage found in servicing existing draft gears is that a sizable inventory or replacement components is required in order to service each of the four different sizes of draft gear pockets currently utilized. By the present arrangement, a new and improved modular mechanism is provided whereby the same modular unit is adapted to be assembled in a multi-pack manner in order to fit the draft gear pocket of the rail car being serviced. Generally speaking, this is accomplished by utilizing whatever number of modular units as may be required to fill the draft gear in question, it being understood that the same basic modular unit may be employed for all sizes of gear pockets.

Not only is versatility one of the outstanding features of the present invention, but also a unique cushioning mechanism is offered to provide the required buff and draft action. This is accomplished by forming each of the unique modular units with both spring or resilient cushion means as well as wedge or friction cushion means.

Accordingly, one of the primary objects of the present invention is to provide a cushioning mechanism comprising an improved modular construction.

Another object of the present invention is to provide a modular cushioning mechanism including a plurality of modules each of which is provided with both spring and friction cushion means.

Another object of the present invention is to provide a draft gear comprising a plurality of modular cushioning elements, the number of which is selected to provide a predetermined buff and draft action according to the size of the gear pocket.

A further object of the present invention is to provide a draft gear adapted for use in all standard size A.A.R. draft pockets and although utilizing conventional draft gear attachments, includes an improved modular cushioning mechanism.

Still another object of the present invention is to provide a draft gear including a plurality of modular cushioning elements whereupon failure of a single such modular element merely requires the replacement of the failed element only.

With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel arrangement, combination and construction of parts hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of the invention is shown in the accompanying drawings, in which:

FIG. 1 is an oblique view diagrammatically illustrating Patented June 2, 1970 a plurality of modular cushioning elements according to the present invention.

FIG. 2 is a horizontal sectional view of a modular cushioning unit according tothe present invention as it appears in the normal or at-rest position.

FIG. 3 is a horizontal sectional View of the structure shown in FIG. 2 as it appears when in the compressed position.

FIG. 4 is a vertical sectional view taken along the line 4-4 of FIG. 2.

FIG. 5 is a compo-site vertical sectional view and discloses in the upper portion thereof the modular unit as it would appear in the compressed position and is taken along the line x-x of FIG. 3; while the lower portion of this figure illustrates the modular unit in the normal position and is taken along the line y-y of FIG. 2.

Similar reference characters designate corresponding parts throughout the several figures of the drawings.

Referring now to the drawings, more particularly FIG. 1, the present invention will be seen to relate to a draft gear comprising a plurality of modules, each generally designated 1, and which are adapted to be utilized in a multi-pack arrangement in sufiicient numbers to fill the conventional yoke 2. In this manner it will be understood that regardless of the size of the draft gear pocket involved in any specific installation, an appropriate number of modules 1 will be used to adequately fill the interior of the yoke 2, and any remaining free space within the yoke will be taken care of by means of a suitable follower or filler block 3. The draft gear rigging will include the usual front stops or lugs 4 and rear stops or lugs 5 which define the length of gear required.

The specific construction of the present improved modules is illustrated in the remaining FIGS. 2-5 of the drawings. Each of the modules 1 comprises a male housing 10 and a female housing 11, both of which are of generally channel construction when viewed from the sides thereof. The overall height of both sections of the housing are of equal dimension; however the male housing 10 will be seen to include a tongue assembly 12 which is adapted to be disposed within a friction pocket 13 comprising an opening extending all the way through the central portion of the female housing 11. As shown in FIG. 5, the top wall 14 and bottom wall 15 of the female housing are co-extensive from one side to the other of the module, while the side walls forming the friction pocket 13 comprise a pair of inclined friction surfaces 16-16 which incline outwardly from the outer edge 13a of the friction pocket 13 to the inner edge 13b thereof. The tongue assembly 12 of the male housing 10 includes a web 17 extending axially within the center of the friction pocket 13 and having a nose 18 extending transversely at the free end thereof. The lateral surfaces of the web 17 comprise a pair of inclined pocket walls 19-19, the inclination of which substantially corresponds to that of the inclined friction surfaces 16-16 of the female housing 11. The nose 18 will be seen to extend laterally a substantial distance from the point of juncture of the nose with the web 17 in a manner to provide a friction shoe pocket 20-20 on each side of the web bounded at the outer end by the lateral portion of the nose 18 and at the inner end by the main body of the male housing.

The friction damping means of the present invention is contained within the friction shoe pockets 20-20- and comprises a U-shaped friction shoe 21 having an outer planar friction surface 22 and including an upper and lower flange 39 which will be seen to be disposed inwardly from the planar surface 22 toward the web 17. Each of the friction shoes 21 is maintained in constant engagement with the inclined friction surfaces 16 of the pocket 13 by suitable spring means disposed between the friction shoe 21 and web 17. As shown most clearly in FIG. 4 of the drawings, this spring means comprises a plurality of curved leaf springs 23, the medial portion of which bears against the web pocket walls 19 While the free ends are directed toward the inner surface 21a of the shoes 21. It will be readily appreciated that any other suitable resilient means may be utilized in place of the leaf springs, such as elastomeric pads. A corresponding longitudinal movement of the shoes 21 and male housing 10 is assured during operation of the invention by engagement of the upper and lower flanges 39 with the lateral extensions 18a of the nose 18.

The outer or side portions of both the female and male housings are cut out to provide a spring pocket 24 within which are disposed a plurality of molded elastomeric units 25. Each of these units 25 comprises a metal plate 26 having an elastomer pad 27 bonded to either face thereof. The aforedescribed elastomeric units 25 are utilized by selecting a sufficient number of these units and arranging them in an assembled manner to fill the space between the opposing end walls 28 of each of the spring pockets 24. The elastomeric units 25 are retained in an axially aligned position by means of a series of protuberances 29 projecting from one side of one pad 27 of each of the units 25 and mating recesses 30 provided in the opposed pad 27 on the side of each unit 25, as will be most clearly seen in the lower portion of FIG. of the drawings. The continuity of this interlocking arrangement is assured by providing a similar protuberance 31 in one of the end walls 28 and a suitable recess 32 in the opposite end wall '28 as shown in this figure of the drawings.

In order to insure maintenance of the axial alignment of the elastomeric units 25 during compression of the module 1 and thus maintain a constant compressive force, a stabilizer pin 33 is disposed through openings 34 provided in the central portion of each of the units 25. A loose sliding fit will be apparent between the stabilizing pin 33 and the surrounding openings 34 to preclude binding therebetween during compression and expansion of the module 1. Additionally, it will be understood that the axial length of the pin 33 will be selected to prevent bottoming of the free ends thereof with the juxtaposed end walls 28-28 when the module is fully compressed as shown in FIG. 3 of the drawings.

When all of the above described components of the present invention have been assembled, the male housing and female housing 11 are retained in an interlocking position by means of a retainer key 35, the free ends of which are positioned within openings 36 formed in the top wall 14 and bottom wall of the female housing 11. The medial portion of the retainer key 35 passes through a key slot 37 provided in the web 17 of the male housing 10. From a review of FIGS. 2, 3 and 5, it will be seen that the key slot 37 extends laterally a substantial distance throughout the web 17. The reason for this construction will become apparent after considering the description hereinafter of the operation of the present invention. The two ends of the key 35 are provided with an offset portion 38 along one and the same side thereof, as shown in FIG. 5.

The modules 1 as above described are positioned in a multi-pack manner within a draft gear pocket by utilizing conventional draft gear attachments such as the yoke 2 shown in FIG. 1. The extent of travel afforded by means of the present invention will be determined primarily by two variables. First, the travel presented by each module 1 is determined by the initial spacing of the opposed wall 11a of the female housing and 10a of the male housing, which spacing is achieved by determation of the longitudinal length of the key slot 37 retaining the twohousing members in interlocking relationship. Of course, the cushioning force available With any one module will be dependent upon the number and construction of both the compression or spring units and spring means 23 forming a part of the friction cushioning means. The other factor affecting the available travel that will be present in a draft gear installation is the total number of modules which will be disposed within the draft pocket.

The operation of the overall arrangement of the present invention will be conventional; that is, upon a draft force being applied to the forward portion of the yoke 2 the yoke will be pulled away from the draft pocket while the axial displacement of the forwardmost module 1 is prevented by means of the fixed front stops 4. Prior to the application of any draft force the module will appear as in the lower section of FIG. 5 and when the module is fully compressed the structure will appear as in the uppermost portion of FIG. 5, wherein it will be seen that the opposed walls 10a and 11a of the two housings are in abutting relationship. At this point, the outer surface of the nose 18 will be disposed flush with the outer face of the female housing 11. Upon the release of the draft force the spring means 25 forces the two housings 10 and 11 apart until the forward vertical edge 35a of the key 35 strikes the forward edge of the key slot 37 as shown in FIG. 2 of the drawings. By reversing the key 35 180 degrees it will be seen that the forward edge 35a will now become the rearward edge of the key and in view of the two offset portions 38 at the ends of the key the edge 35b will now become the forward edge. Due to the recessed nature of the edge 35b the forward portion of the slot 37 now be positioned a greater distance to the rear, which displacement increases the distance between the opposed walls and 11a of the two housings in order to increase the available travel a corresponding amount.

The operation of the modules 1 under a buff force will be exactly the same as the above described sequence under draft as the rearwardmost module strikes the rear stops 5.

I claim:

1. In a railway draft rigging, a yoke containing a plurality of cushioning modules each comprising, juxtaposed male and female housings, said female housing provided with a pocket having oppositely disposed inclined surfaces, a web projecting from said male housing into said pocket, friction means carried by said web and normally spring urged into engagement with said pocket surfaces, said inclined pocket surfaces diverging from one another from the outer edge of said pocket to the edge of said pocket juxtaposed said male housing, the opposed walls of said web substantially parallel to said inclined pocket surfaces, said housings both provided with oppositely disposed spring pockets having facing end walls, spring cushion means mounted in said pockets between said end walls and normally urging said housings into a spaced apart relationship, and means locking said housings together and permitting limited axial displacement between said housings.

2. A railway draft rigging, according to claim 1, wherein, said web includes a laterally extending nose at the free end thereof which provides with said web walls a pocket for said friction means.

3. A railway draft rigging, according to claim 2, wherein, said friction means includes a shoe having an outer friction surface spring urged into contact with said inclined surfaces of said female housing pocket.

4. A railway draft rigging, according to claim 1, wherein, said spring cushion means includes a resilient element having stabilizing means insuring axial alignment of said element during compression and expansion thereof.

5. A railway draft rigging, according to claim 4, wherein, said resilient element is provided with an axial opening and said stabilizing means includes a longitudinal pin freely disposed through said opening, whereby, when said housings are compressed into abutment the two ends of said pin will not bottom against said end walls.

6. A railway draft rigging, according to claim 1, wherein, said spring cushion means includes a plurality of axially aligned resilient compressive elements.

7. A railway draft rigging, according to claim 6 wherein each of said elements comprises a pair of elastomeric pads having a rigid plate sandwiched therebetween, said pads having substantially planar faces, and means interlocking adjacent ones of said elements to insure lateral stability of said elements during compression and expansion thereof.

8. A railway draft rigging, according to claim 1, wherein the top and bottom of said female housing is provided with an opening and said web includes an elongated slot therethrough intermediate said female housing openings, and said locking means comprises a retaining key disposed through said openings and slot.

9. A railway draft rigging, according to claim 8, where- References Cited UNITED STATES PATENTS 2,260,532 10/ 1941 Lindeman. 2,555,431 6/1951 Withall 2l322 X 2,686,667 8/1954 Willison et al.

ARTHUR L. LA POINT, Primary Examiner 

